While ramping up the fight against al Qaeda with U.S. help, the Yemeni government has also escalated its own internal conflicts in the north and south that threaten to throw the fractured country into greater chaos and even nourish the terror group's growth.

Yemeni troops backed with tanks and artillery launched new assaults against Shiite rebels, the military said Saturday, the latest offensive in an increasingly bloody war that has been raging for years on the capital's northern doorstep.

Also, lethal clashes erupted last week between protesters and security forces struggling to put an end to a secessionist movement in the once-independent south, where bitterness toward Sanaa is swelling.

Observers question if the impoverished nation's military can wage a determined campaign against al Qaeda under the strain of the multiple conflicts, and there are fears the terror group is seeking to link up with insurgents for new recruits, particularly in the south.

The United States, which is funneling millions of dollars to Yemen's government to fight al Qaeda, is pressing Sanaa to resolve its internal turmoil and focus on the terror group. Washington warns that the al Qaeda offshoot here has become a global threat after it allegedly plotted a failed attempt to bomb a U.S. passenger jet on Christmas.

What fuels Yemen's instability is widespread alienation among tribes and factions toward a regime they complain has for years hoarded power and wealth among a small circle of supporters. They say their regions have been neglected, with poverty spreading and infrastructure left to deteriorate.

The provinces of the south were an independent nation for decades, ruled by a socialist regime, until it unified with the north in 1990. Four years later, Sanaa put down a new independence bid in a three-month civil war.

In the north, Shiite rebels known as Hawthis rose up against the government in 2004. Since August, the conflict escalated into full-fledged warfare, centered in the mountainous corner of Yemen between Sanaa and the Saudi border.